Surgical Outcomes for Mastectomy Patients Receiving Neoadjuvant Chemotherapy: A Propensity-Matched Analysis

To evaluate the risk of neoadjuvant chemotherapy for surgical morbidity after mastectomy with or without reconstruction using 1:1 matching.

Postoperative surgical complications remain a potentially preventable event for breast cancer patients undergoing mastectomy. Neoadjuvant chemotherapy is among variables identified as contributory to risk, but it has not been rigorously evaluated as a principal causal influence.

Data from American College of Surgeons National Surgical Quality Improvement Program (2006-2012) were used to identify females with invasive breast cancer undergoing planned mastectomy. Surgical cases categorized as clean and undergoing no secondary procedures unrelated to mastectomy were included. A 1:1 matched propensity analysis was performed using neoadjuvant chemotherapy within 30 days of surgery as treatment. A total of 12 preoperative variables were used with additional procedure matching: bilateral mastectomy, nodal surgery, tissue, and/or implant. Outcomes examined were 4 wound occurrences, sepsis, and unplanned return to the operating room.

We identified 31,130 patient procedures with 2488 (7.5%) receiving chemotherapy. We matched 2411 cases, with probability of treatment being 0.005 to 0.470 in both cohorts. Superficial wound complication was the most common wound event, 2.24% in neoadjuvant-treated versus 2.45% in those that were not (P = 0.627). The rate of return to the operating room was 5.7% in the neoadjuvant group versus 5.2% in those that were not (P = 0.445). The rate of sepsis was 0.37% in the neoadjuvant group versus 0.46% in those that were not (P = 0.654).

This large, matched cohort study, controlled for preoperative risk factors and most importantly for the surgical procedure performed, demonstrates that breast cancer patients receiving neoadjuvant chemotherapy have no increased risk for surgical morbidity.